Tretinoin

Key points

• Sun sensitivity is the main precaution: tretinoin makes skin more reactive to UV light, so exposure to sunlight and sunlamps should be minimised during use, and the product should not be applied to sunburned skin until it has healed.
• Some people using RETIN-A notice the treated area become lighter or darker than usual; the label describes this pigment change as reversible.
• Melacare Forte pairs tretinoin 0.025% with hydroquinone 4% and mometasone furoate 0.1%, making it the only combination product on this shelf; the other three are single-ingredient tretinoin creams.

How does Tretinoin work?

Tretinoin (all-trans retinoic acid) is a natural metabolite of retinol, or vitamin A. Applied to the skin, it speeds up the turnover of cells in the hair follicle, the tiny structure that traps oil and dead skin to form a blocked pore.

The exact mechanism is not fully understood, but current evidence suggests tretinoin reduces the stickiness between these cells and increases their division rate. This pushes existing blocked pores out and prevents new ones from forming. Absorption through the skin is minimal, with plasma levels undetectable in most people tested, so the action stays local.

Brands and forms in this catalogue

Retin-A is the original brand-name tretinoin cream. The two generic tretinoin creams at 0.025% and 0.05% contain the same active ingredient in the same cream base. All three come in 20 g tubes.

Melacare Forte, made by Ajanta Pharma, is a different kind of product: it combines tretinoin 0.025% with hydroquinone 4% and mometasone furoate 0.1% in a 25 g tube. It is listed under Melasma in the catalogue, though the tretinoin labels themselves indicate acne vulgaris only. All four products fall under Skin Care.

Further reading

• RETIN-A- tretinoin cream RETIN-A- tretinoin gel
• Treclin 1 %/0.025 % w/w Gel
• Tretinoin: MedlinePlus Drug Information